Synthetic bicomponent fibers comprising poly(ethylene terephthalate) and poly(trimethylene terephthalate) are known. Such fibers are disclosed, for example, in U.S. Pat. No. 3,671,379, International Published Application No. WO01/53573, European Published Patent Application No. EP1059372, and Japanese Published Patent Application JP61-032404. In addition, Japanese Published Patent Application Nos. JP49-124333, JP51-037376, and JP2002-54034 disclose methods of treating polyester bicomponent fibers. However, these and other methods of treating bicomponent fibers can result in fibers that have crimp values that are too high for satisfactory further processing. Accordingly, new methods of processing such fibers are sought.